Method to detect application spoofing in mixed use avionics display

ABSTRACT

A method to detect application spoofing in a mixed use avionics display by indicating when a mixed use avionics display is displaying information from a non-certified source. The method comprises providing an avionics display having a display area that is capable of displaying information from a non-certified source. A data connection is established between the non-certified source and the avionics display. Information is provided from the non-certified source to the avionics display through the data connection. The information from the non-certified source is then displayed on the display area so that less than then entire display area is used in displaying the information. The displaying of information from the non-certified source on less than then the entire display area gives a visual indication that the information being displayed on the avionics display is from a non-certified source and susceptible to interference by a remote party and possible application spoofing.

TECHNICAL FIELD OF THE INVENTION

[0001] The present invention relates to methods of detecting applicationspoofing in a mixed use avionics display, such as a certified flightdeck display.

BACKGROUND OF THE INVENTION

[0002] Airlines rely upon flight manuals, procedural manuals, and othermanuals in the operation of its aircraft. These manuals are continuallybeing revised, modified and supplemented by the airlines to maintaincurrent standards for operation of the aircraft. These manuals arecarried on the aircraft in paper form and are quite extensive in sizeand weight. The various manuals that are used in operating aircraft canweigh 100 pounds or more. Every pound of materials carried by anaircraft increases fuel consumption and the cost to operate theaircraft. Airlines are constantly looking for ways to reduce theiroperating costs and therefore it is desirable to minimize the weightthat must be carried by the aircraft.

[0003] In an effort to reduce the weight of these manuals, airlines areincreasingly relying upon the use of these manuals in electronic format.The manuals are converted into computer applications that are modifiableby the airlines, hereinafter referred to as Airline Modifiable Software(AMS). The AMS must receive approval from the regulatory agencies thatoversee aircraft operation, such as the Federal Aviation Administration.These regulatory agencies approve the AMS for use in lieu of the papermanuals. In order to utilize the AMS, a display is required that can beviewed by the flight crew at various times during the operation of theaircraft.

[0004] The flight deck on an aircraft has numerous certified flight deckdisplays upon which the AMS could potentially be displayed. However, theAMS applications are not certified and are therefore not currentlyallowed to be displayed on a certified flight deck display. As apossible solution, an aircraft manufacturer could install additionalcertified displays on the flight deck that are dedicated to displayingthe AMS. However, space is extremely limited on the flight deck andcertified displays are expensive to build and have certified.Additionally, certified displays have been shown to not be costeffective when limited to non-essential functions, such as the AMS.

[0005] Another potential problem with using an existing certified flightdeck display to display the AMS is that the AMS applications must beprevented from affecting the safe operation of the aircraft. AMSapplications are increasingly expected to be provided by sources thatare not in or on the flight deck. For example, AMS applications can beprovided by an airline-controlled server which is installed on theairplane. However, the airline-controlled server may at times (duringflight crew access or not) be connected to off board networks. Thesenetworks are open and therefore susceptible to malicious interference byremote parties that may go undetected. Because these networks are open,there is a possibility that a remote party could maliciously interferewith the safe operation of the aircraft by interfering with thedisplaying of the AMS on the existing certified display. For example,the malicious remote party could design an application that emulates orspoofs the certified display and have that application appear on thecertified display with incorrect data instead of the AMS. The flightcrew would think that the certified display was displaying theinformation for which the display is certified and believe that theinaccurate data is true and subsequently affect the safe operation ofthe aircraft.

[0006] Therefore, to limit the possibility of malicious interference byremote parties airlines have relied upon the use of carry-on personalelectronic devices (PEDs), such as laptop computers, to run the AMSapplications. The PED's could avoid the possibility of maliciousinterference by remote parties if the PED's were never connected to opennetworks. However, most PED's are at sometime connected to open networksand, therefore, exposed to malicious interference which may not bedetected. The use of PEDs are also not without substantial drawbacks. Asstated above, space is limited on a flight deck and the PEDs caninterfere with the operation of the flight deck controls, particularlythe control column. Additionally, the PEDs could present a hazard duringturbulence in that the PEDs may injure a member of the flight crew ordamage equipment. Furthermore, PEDs cannot be used during some phases offlight during which it may be desirable to have the AMS applicationsdisplayed. Finally, some PEDs will not be bright enough for sunlitconditions nor dim enough for nighttime use to facilitate efficient andcomfortable use by members of the flight crew.

[0007] Therefore, it would be advantageous to an airline if it could usea certified flight deck display to display the AMS applications whilepreventing or at least detecting malicious interference by remoteparties.

SUMMARY OF THE INVENTION

[0008] The present invention is directed to a method and apparatus thatallows the mixed use of a certified avionics display to displayinformation received from a non-certified source while allowing thedetection of application spoofing, in accordance with preferredembodiments of the present invention. The method involves providingvisual indications on the avionics display that alerts a member of theflight crew when the avionics display is being used to displayinformation from a non-certified source and, therefore, may not besecure and is subject to potential malicious interference by a remoteparty.

[0009] In one preferred embodiment, the method comprises the providingof an avionics display that has a display area capable of displayinginformation from a non-certified source. Information from thenon-certified source is provided to the avionics display by a dataconnection. The information from the non-certified source is thendisplayed on the display area so that less than the entire display areais used in displaying the information. Because less than the entiredisplay area is used to display the information from the non-certifiedsource, a member of the flight crew, when observing the avionicsdisplay, will be able to visually detect that the avionics display iscurrently being used to display information from a non-certified sourceand, as such, is susceptible to malicious interference by a remoteparty. Additionally, because the information is displayed on less thanthe entire display area, any attempt by a remote party to emulate orspoof the certified display for which the avionics display is certifiedwould appear on less than the entire display area, unlike the certifieddisplay which appears on the entire display area, and would furtherindicate that the avionics display is not displaying the certifieddisplay, but rather is displaying information from the non-certifiedsource and that application spoofing is occurring. Therefore, a memberof the flight crew will avoid being misled by application spoofingoccurring on the mixed use avionics display and can avoid any safetyhazards which would have resulted from an undetected applicationspoofing.

[0010] Optionally, but preferably, the display area is partitioned sothat at least a portion of the display area can not display theinformation from the non-certified source. The information from thenon-certified source would then be displayed on less than the entiredisplay area. The partitioning can be accomplished by providing thenon-certified source of information with a false indication of the sizeof the display area. Because the non-certified source of informationdoes not know the true size of the display area, the non-certifiedsource is not capable of addressing the entire display area and,therefore, not capable of using the entire display area to display theinformation. Another method of partitioning the display area is byproviding an avionics display that comprises a microprocessor. Themicroprocessor partitions the display area by limiting the area in whichthe information from the non-certified source can be displayed. Becausethe display area is partitioned by the microprocessor, information beingprovided from the non-certified source is not capable of being displayedon the entire display area and provides a visual indication to theflight crew of when the avionics display is displaying information fromthe non-certified source and is vulnerable to application spoofing.

[0011] In a different aspect of the present invention, the mixed useavionics display displays the certified display for which it iscertified on the display area. The certified display is maintained onthe display area while the avionics display simultaneously displays theinformation from the non-certified source. The information from thenon-certified source is displayed on the display area in front of thecertified display so that the information is visible on the avionicsdisplay and at least a portion of the certified display is also visibleon the avionics display. A member of the flight crew is then able to seeboth a portion of the certified display and the display of theinformation from the non-certified source at the same time, and will beable to visually ascertain when information from the non-certifiedsource is being displayed and if application spoofing is occurring.

[0012] In another aspect of the present invention, a visual indicator isdisplayed on the display area of the avionics display wheneverinformation from a non-certified source is being displayed. Thedisplaying of the information from the non-certified source is preventedfrom blocking the visual indicator so that the visual indicator isalways visible on the display area when the information is beingdisplayed. The flight crew will then have a visual indication of whenthe avionics display is displaying information from a non-certifiedsource and is subject to malicious interference by a remote party andpotential application spoofing.

[0013] In a different aspect of the present invention, applicationspoofing during critical periods of operation of an aircraft is avoidedby preventing the displaying of information from a non-certified sourceon the avionics display during critical periods of operation. The methodis accomplished by establishing rules that dictate when the avionicsdisplay can display information from a non-certified source. Theavionics display is then prevented from displaying the information whenthe rules dictate that the avionics display should not display theinformation so that application spoofing can not occur. The rules can beestablished to correspond to applicable government regulations thatgovern the operation of an aircraft employing mixed use avionicsdisplays. Additionally, the rules can go beyond the requirements of thegovernment regulations and also dictate that the avionics display beprevented from displaying information from a non-certified source duringany desired period of operation of the aircraft.

[0014] Further areas of applicability of the present invention willbecome apparent from the detailed description provided hereinafter. Itshould be understood that the detailed description and specificexamples, while indicating the preferred embodiment of the invention,are intended for purposes of illustration only and are not intended tolimit the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention will become more fully understood from thedetailed description and the accompanying drawings, wherein:

[0016]FIG. 1 is a simplified block diagram drawing illustrating thecomponents of the avionics display and its communication with anon-certified source of information;

[0017]FIG. 2 is a simplified diagram showing the communication betweenan aircraft and a non-certified source of information that is externalto the aircraft;

[0018] FIGS. 3A-C are drawings of the visual display unit of FIG. 1showing various methods of partitioning the display area;

[0019]FIG. 4 is a drawing of the visual display unit of FIG. 1 showingthe simultaneous displaying of a certified display and of informationfrom a non-certified source;

[0020] FIGS. 5A-B are drawings of the visual display unit of FIG. 1showing the use of a visual indicator on the display to indicate thedisplaying of information from a non-certified source; and

[0021]FIG. 6 shows the use of rules to control when information from anon-certified source can be displayed on the avionics display of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] The following description of the preferred embodiment(s) ismerely exemplary in nature and is in no way intended to limit theinvention, its application, or uses.

[0023] Referring to FIG. 1, there is shown a simplified diagram of atypical avionics display 20 used in an aircraft 22. The avionics display20 comprises a microprocessor 24 that provides information to a visualdisplay unit 26. The visual display unit 26 has a display area 28 thatis capable of displaying information received from the microprocessor24.

[0024] In a certified flight deck display the avionics display 20 isdedicated to only displaying a certified display. These certified flightdeck displays only receive information from certified sources on theaircraft 22 and not from a non-certified source 30. Because thecertified flight deck display only receives information from thecertified sources on the aircraft, there is no possibility of maliciousinterference with the certified flight deck display by a remote party.The avionics display 20 in FIG. 1 is a mixed use avionics display inthat it is capable of displaying a certified display and of displayinginformation from a non-certified source 30. The avionics display 20communicates with the non-certified source 30 via a data connection 31.The data connection 31 allows two way communication between the avionicsdisplay 20 and the non-certified source 30 so that a member of theflight crew can request and retrieve desired information from thenon-certified source 30. The data connection 31 between the avionicsdisplay 20 and the non-certified source 30 can be by any means known tothose skilled in the art.

[0025] The non-certified source 30 is preferably used to run the AMSapplications and to provide these applications to the flight deck viathe avionics display 20. The non-certified source 30 can be any sourceof information that is not a certified source of information. Forexample, the non-certified source 30 could be a portable computercarried on board the aircraft 22 and connected to the avionics display20 by the data connection 31. The non-certified source 30 could also bean airline-controlled server which is installed on the aircraft 22.Additionally, the non-certified source 30 could also be located externalto the aircraft 22. For example, the non-certified source 30 could be aserver which runs the AMS software and is located in a ground basedstructure. In this case, the data connection 31 connects the avionicsdisplay 20 to the non-certified source 30 via wireless communication, asis known in the art. The non-certified source 30 is not certified aspart of the aircraft's 22 type design. These non-certified sources mayat times be connected to other sources that are open to remote parties.Because the non-certified source 30 may be exposed to an openconnection, there is a potential for malicious interference with theinformation being sent from the non-certified source 30 to the avionicsdisplay 20. Thus, the non-certified source 30 can be exposed tomalicious interference by a remote party which may not be detected by amember of the flight crew. The present invention allows a flight crewmember to detect when the visual display unit 26 is displaying on thedisplay area 28 information from the non-certified source 30. The flightcrew member then knows that the information being provided should notemulate or spoof the certified display for which the avionics display 20is certified.

[0026] In one aspect of the invention, as shown in FIG. 1, thedisplaying of the information from the non-certified source 30 on thedisplay area 28 does not occupy the entire display area 28 so that theinformation from the non-certified source 30 is only displayed on afirst portion 32 of the display area 28. More preferably, as shown inFIGS. 3A-C, the display area 28 is partitioned so that a second portion34 of the display area cannot display the information from thenon-certified source 30. The partitioning of the display area 28 intofirst and second portions 32, 34 can be accomplished in a number ofdifferent ways. Preferably, the partitioning of the display area 28 isaccomplished by providing the non-certified source 30 with a falseindication of the size of the display area 28 so that the non-certifiedsource 30 is not capable of addressing the entire display area 28. Asshown in FIG. 3A, providing the non-certified source 30 with a falseindication of the size of the display area 28 can be accomplished byproviding the non-certified source 30 with a false 0,0 corner displayaddress 36 so that the non-certified source 30 is not capable ofaddressing the entire display area 28. Another way of partitioning, asshown in FIG. 3C, is by providing the non-certified source 30 with afalse horizontal display size 38 so that the non-certified source 30 isnot capable of addressing the entire display area 28. Still another wayof partitioning, as shown in FIG. 3B, is by providing the non-certifiedsource 30 with a false vertical display size 40 so that thenon-certified source 30 is not capable of addressing the entire displayarea 28. While the method of partitioning the display area 28 byproviding the non-certified source 30 with a false indication of thesize of the display area 28 has been described as being accomplished byproviding a false 0,0 corner display address 36, a false horizontaldisplay size 38, and a false vertical display size 40, it should beunderstood that these methods are not mutually exclusive and can becombined in various combinations without departing from the scope of theinvention. It should also be pointed out that the methods described areequally applicable to providing a false indication of the size of thedisplay area 28 when other than Cartesian coordinates are used toaddress the display area 28, such as when polar coordinates are used.

[0027] An alternative way to partition the display area 28 so that thenon-certified source 30 can not be displayed on the entire display area28 is by use of the microprocessor 24. In this aspect of the invention,the non-certified source 30 can be provided with a correct indication ofthe size of the display area 28 but the microprocessor 24 limits thesize of the first portion 32 for displaying information from thenon-certified source 30 to less than the size of the entire display area28 so that the second portion 34 of the display area can not be used todisplay information from the non-certified source 30. Regardless ofwhich method is employed, the result is that only the first portion 32of the display area 28 displays information from the non-certifiedsource 30 while the second portion 34 of the display area 28 does notdisplay information from the non-certified source 30 and therebyprovides for a visual indication of when the avionics display 20 isdisplaying information from the non-certified source 30 and susceptibleto application spoofing.

[0028] In another aspect of the invention, as shown in FIG. 4, theavionics display 20 has a certified display 42 displayed on the entiredisplay area 28 at all times. The certified display 42 is maintained onthe display area 28 while the information from the non-certified source30 is simultaneously displayed on the first portion 32 of the displayarea 28. In this aspect of the invention, the information from thenon-certified source 30 is displayed in front of or superimposed on thecertified display 42 so that the information from the non-certifiedsource 30 is visible on the avionics display 20 and at least a portion43 of the certified display 42 is also visible on the avionics display20. In this manner, a member of the flight crew, when visuallyperceiving the avionics display 20, will always see the portion 43 ofthe certified display 42 along with the information from thenon-certified source 30 being displayed in front of or superimposed onthe certified display 42 and know that the avionics display 20 issusceptible to application spoofing.

[0029] In yet another aspect of the invention, as can be seen in FIGS.5A-B, a visual indicator 44 is displayed on the display area 28 wheneverinformation from the non-certified source 30 is being displayed on theavionics display 20. The visual indicator 44 is displayed on the displayarea 28 in a manner that does not allow the displaying of informationfrom the non-certified source 30 to block the visual indicator 44 sothat visual indicator 44 is always visible on the display area 28 whenthe information from the non-certified source 30 is being displayed. Thevisual indicator 44 can be displayed on the display area 28 outside ofthe first portion 32 of the display area 28 that is displaying theinformation from the non-certified source 30. Alternatively, the visualindicator 44 can be displayed on the first portion 32 of the displayarea 28 that is displaying the information from the non-certified source30. When the visual indicator 44 is displayed on the first portion 32 ofthe display area 28 that displays the information from the non-certifiedsource 30, the visual indicator 44 is in front of or superimposed on theinformation so that the visual indicator 44 is always visible on thedisplay area 28 whenever the information from a non-certified source 30is being displayed on the avionics display 20. While the visualindicator 44 is shown as being an asterik, it should be understood thatthe visual indicator 44 does not need to be in the form of an asterik.For example, the visual indicator 44 can be another shape or even a bandalong the display or a frame that surrounds the display.

[0030] While the visual indicator 44 has been described as beingdisplayed on the avionics display 20 in the display area 28, it is alsopossible to have the visual indicator 44 appear on the avionics display20 but not in the display area 28. For example, the visual indicator 44could be a light or some other indicator on the avionics display whichwould light up, glow, or, in some other fashion, indicate when theinformation being displayed on the avionics display 20 is from anon-certified source 30. However, having the visual indicator 44 notappear on the display area 28 presents a potential problem in that thevisual indicator 44 could malfunction while the visual display unit 26continues to function properly and a member of the flight crew couldbelieve that the information being displayed on the display area 28 is acertified display when in reality the avionics display 20 is displayinginformation from a non-certified source 30 and could be susceptible toapplication spoofing. By having the visual indicator 44 appear on thedisplay area 28 the visual indicator 44 will function when the visualdisplay unit 26 is functioning and inform the flight crew wheninformation is being displayed from the non-certified source 30. In thismanner, the problem associated with a visual indicator that operatesindependently of the visual display unit 26 is avoided.

[0031] Another method of preventing application spoofing in a mixed useavionics display 20 is accomplished by establishing rules that dictatewhen the avionics display 20 can display information from thenon-certified source 30 and when it can not. The avionics display 20 isthen prevented from displaying information from the non-certified source30 when the rules dictate that the avionics display 20 should not bedisplaying information from a non-certified source 30, such as when theaircraft 22 is in critical stages of operation.

[0032] Preferably, the rules are established based upon applicablegovernment regulations that govern the operation of the aircraft 22.These rules can vary for each type of aircraft 22. The rules can also bemodified as various government regulations change. Additionally, therules can also be established based upon the particular safety protocolsthe owner of the aircraft 22 desires to implement in the operation ofthe aircraft 22. The rules would then dictate when a member of theflight crew would have access to viewing information from thenon-certified source 30 on the avionics display 20. Because theapplicable government regulations would require the avionics display 20to display the certified display 42 on the visual display unit 26 duringcritical periods of operation of the aircraft 22, any maliciousinterference by a remote party would not occur during these criticalperiods of operation and application spoofing would not be a concern forthe safe operation of the aircraft 22.

[0033] Referring now to FIG. 5, when a request is made by a member ofthe flight crew to view information from the non-certified source 30,the microprocessor 24 checks the rules to see if the rules allow for thedisplaying of information from the non-certified source 30 on theavionics display 20 during that stage of operation of the aircraft 22.If the rules indicate that information from the non-certified source 30can be displayed on the avionics display 20, the microprocessor 24allows the requested information from the non-certified source 30 to bedisplayed on the avionics display 20. Because the operational conditionof the aircraft 22 is dynamic, when the avionics display 20 isdisplaying information from the non-certified source 30, themicroprocessor 24 continues to monitor the operation of the aircraft 22and compare the current status of the operation of aircraft 22 to therules to ensure that it is still acceptable to display information fromthe non-certified source 30 on the avionics display 20. Microprocessor24 can be programmed to intermittently and/or continuously monitor theoperational condition of the aircraft 22 to perform this function. Forexample, the microprocessor 24 can be programmed to compare theoperation of the aircraft 22 to the rules every 30 seconds, 60 seconds,120 seconds, or what ever time interval is deemed appropriate to ensurethe safe operation of the aircraft 22 and to prevent maliciousinterference by a remote party during critical stages of operation ofthe aircraft 22. Alternatively, the microprocessor 24 could beprogrammed to continuously monitor the operational status of theaircraft 22 and compare the operational status to the rules so that whenthe operational status of aircraft 22 changes to a condition wherein theavionics display 20 should not be displaying information from thenon-certified source 30, the microprocessor 24 immediately prevents thedisplaying of information from the non-certified source 30.

[0034] When the rules indicate that information from the non-certifiedsource 30 is not allowed to be displayed on the avionics display 20, themicroprocessor 24 causes the avionics display 20 to display thecertified display 42 for which it is certified and prevents thedisplaying of information from the non-certified source 30. Optionally,the microprocessor 24 could also be programmed to terminate the dataconnection 31 which is providing the information from the non-certifiedsource 30 to the avionics display 20. The termination of the dataconnection 31 eliminates the possibility of malicious interference by aremote party with the avionics display 20. While the use of rules todictate when information from the non-certified source 30 can bedisplayed on the avionics display 20 has been described with referenceto the steps shown in FIG. 6, it should be understood that FIG. 6 is anexample and there are other ways to use the rules to control wheninformation from a non-certified source 30 is allowed to be displayed onthe avionics display 20.

[0035] While the invention has been described in reference to allowingthe displaying of AMS applications on the avionics display 20, it shouldbe understood that the method is equally applicable to allowing thedisplaying of other applications from a non-certified source on theavionics display 20, such as from the internet.

[0036] The description of the invention is merely exemplary in natureand, thus, variations that do not depart from the gist of the inventionare intended to be within the scope of the invention. Such variationsare not to be regarded as a departure from the spirit and scope of theinvention.

What is claimed is:
 1. A method of detecting application spoofing in amixed use avionics display by indicating when the mixed use avionicsdisplay is displaying information from a non-certified source, themethod comprising the steps of: providing an avionics display having adisplay area that is capable of displaying information from anon-certified source; providing a data connection between the avionicsdisplay and the non-certified source; providing information from thenon-certified source to the avionics display; and displaying theinformation on the display area so that less than the entire displayarea displays the information.
 2. The method of claim 1, furthercomprising the step of: partitioning the display area so that at least aportion of the display area cannot display the information from thenon-certified source.
 3. The method of claim 2, wherein the step ofpartitioning the display area further comprises the step of: providingthe non-certified source with a false indication of the size of thedisplay area so that the non-certified source is not capable ofaddressing the entire display area.
 4. The method of claim 3, whereinthe step of providing the non-certified source with a false indicationof size further comprises the step of: providing the non-certifiedsource with a false display address so that the non-certified source isnot capable of addressing the entire display area.
 5. The method ofclaim 3, wherein the step of providing the non-certified source with afalse indication of size further comprises the step of: providing afalse horizontal display size so that the non-certified source is notcapable of addressing the entire display area.
 6. The method of claim 3,wherein the step of providing the non-certified source with a falseindication of size further comprises the step of: providing a falsevertical display size so that the non-certified source is not capable ofaddressing the entire display area.
 7. The method of claim 2, whereinthe avionics display is comprised of a visual display monitor and acomputer processor and the step of partitioning the display area furthercomprises the step of: the computer processor limiting the display areain which the information can be displayed.
 8. The method of claim 1,further comprising the steps of: displaying a certified display on thedisplay area; and maintaining the displaying of the certified display onthe display area while simultaneously displaying the information fromthe non-certified source; and the step of displaying the information onthe display area further comprises displaying the information on thedisplay area in front of the certified display so that the informationis visible on the avionics display and at least a portion of thecertified display is visible on the avionics display.
 9. The method ofclaim 1, further comprising the steps of: displaying a visual indicatoron the display area whenever the information is being displayed; andpreventing the displaying of the information from blocking the visualindicator so that the visual indicator is always visible on the displayarea when the information is being displayed.
 10. The method of claim 9,wherein the step of preventing the displaying of the information fromblocking the visual indicator further comprises the step of: displayingthe visual indicator on a portion of the display area that is not usedto display the information so that the visual indicator is alwaysvisible when displaying the information.
 11. The method of claim 9,wherein the step of preventing the displaying of the information fromblocking the visual indicator further comprises the step of:superimposing the visual indicator in front of the information beingdisplayed so that the visual indicator is always visible when displayingthe information.
 12. A method of preventing application spoofing in amixed use avionics display, the method comprising the steps of:providing an avionics display that is capable of displaying informationfrom a non-certified source; establishing rules that dictate when theavionics display can display the information; and preventing thedisplaying of the information when the rules dictate that the avionicsdisplay should not display the information so that application spoofingcan not occur.
 13. The method of claim 12, wherein the step ofestablishing the rules further comprises the steps of: reviewingapplicable government regulations that govern the operation of anaircraft; and determining when the regulations require the avionicsdisplay to display a certified display.
 14. The method of claim 12,wherein the step of establishing the rules further comprises:identifying periods of operation of an aircraft when an operator of theaircraft should not be allowed to access the information.
 15. The methodof claim 12, wherein the avionics display comprises a computer processorand the processor performs the step of preventing the displaying of theinformation from the non-certified source.
 16. The method of claim 12,wherein the step of preventing the displaying of the information furthercomprises the step of: terminating a data connection between theavionics display and the non-certified source of information so that theavionics display does not receive information from the non-certifiedsource.
 17. A method of allowing an aircraft certified flight deckdisplay to be used as a mixed use avionics display by indicating whenthe certified flight deck display is displaying information from anon-certified source, the method comprising the steps of: providing anaircraft having a certified flight deck display; providing a dataconnection between the certified flight deck display and a non-certifiedsource of information; providing information from the non-certifiedsource to the certified flight deck display; limiting space on thecertified flight deck display in which the information can be displayedso that an entire display area is not used to display the information;and displaying the information in the limited space on the certifiedflight deck display.
 18. The method of claim 17, wherein the step oflimiting the space on the certified flight deck display in which theinformation can be displayed further comprises the step of: partitioningthe display area so that at least a portion of the display area can notdisplay the information from the non-certified source.
 19. The method ofclaim 18, wherein the step of partitioning the display area furthercomprises the step of: providing the non-certified source with a falseindication of the size of the display area so that the non-certifiedsource is not capable of addressing the entire display area.
 20. Themethod of claim 17, further comprising the steps of: displaying acertified display on the display area; displaying the information fromthe non-certified source on the display area in front of the certifieddisplay; and maintaining the displaying of the certified display on thedisplay area while simultaneously displaying the information from thenon-certified source so that the information is visible on the certifiedflight deck display and at least a portion of the certified display isvisible on the certified flight deck display.
 21. The method of claim17, further comprising the steps of: placing a visual indicator on thedisplay area whenever the information is being displayed; and preventingthe displaying of the information from blocking the visual indicator sothat the visual indicator is always visible on the display area when theinformation is being displayed.